Apparatus for grinding cylindrical surfaces



Jan. 12, 1932. I c, -r0 1,840,720

APPARATUS FOR GRINDING CYLINDRICAL SURFACES Filed Feb.- 9, 1929 Sheets-Sheet l Zjmwmt z I 3% Jan. 12, 1932. Q HUTTQ 1,840,720

APPARATUS FOR GRINDING CYLINDRICAL SURFACES Filed Feb. 9, 1929 6 Sheets-Sheet 2.

L Jnoantox c. HUTTO' Jan. 12, 1932.

' APPARATUS FOR GRINDING CYLINDRICAL SURFACES Filed Feb. 9, 1929 6 Sheets-Sheet 5 f M w r 1 m m n 6 m Jan. 12, 1932. c, HUTTQ 1,840,720

APPARATUS FOR GRINDING CYLINDRICAL SURFACES Filed Feb. 9, 1929 6 Sheets-Sheet 4 gnwwhn am WM Jan. 12, 1932. M. c. HUTTO 1,840,720

APPARATUS FOR GRINDING CYLINDRICAL SURFACES Filed Feb. 9, 1929 6 Sheets-Sheet 5 Jan. 12, 1932. M, c. HUTTO 1,840,720

APPARATUS FOR GRINDING CYLINDIMCAL SURFACES Filed Feb. 9 A929 6 Sheets-Sheet 6 WA/Mm G QE W Patented Jan. 12, 1932 UNITED STATES PATENT OFFICE MARSD'EN C. I-IUTTO, OF DETROIT, MICHIGAN, ASSIGNOB T0 I-IUTTO ENGINEERING COMI- IPANY, INC., OF DETROIT, MICHIGAN, A. CORPORATON OF MICHIGAN APPARATUS FOR GRINDING CYLINDRICAL SURFACES Application filed February 9, 1929. Serial No. 338,746.

This invention relates to a cylinder grinder which is more particularly adapted to grind ing cylindrical surfaces of large diameter, al though the same can also be used for grinding cylindrical surfaces of relatively small diameter.

The object of this invention is to provide a grinder for this purpose which is strong, light and easily operable and which can be readily used for grinding either external or internal cylindrical surfaces and thereby materially reduce the cost of the equipment for doing this character of work.

In the accompanying drawings Figure 1 is a longitudinal section of a grinder embodying my invention and organized for grinding internal cylindrical surfaces.

Figure 2 is a fragmentary outside View thereof.

Figure 3 is a View from one end of the apparatus shown in Fig. 1.

Figure 4 is a fragmentary longitudinal section taken on line P4 Fig. 3.

Figure 5 is a view from the other end of the apparatus shown in Fig. 1.

Figure 6 is a fragmentary cross section taken on line 66 Fig. 1.

Figure 7 is a longitudinal section of the grinder containing my improvements and organized for grinding external cylindrical surfaces.

Figure 8 is a fragmentary inside vieW in Fig. 7, looking at that end opposite to the one shown in Fig. 9.

In the following description similar characters of reference indicate like parts in the several figures of the drawings.

As shown in Figs. 16 the tool is organized for grinding and polishing internal cylindrical surfaces, such as the bore of a cylinder 20 shown by dotted lines in Fig. 1, and in Fi 7l1 the same is organized for grinding or polishing external cylindrical surfaces such as the periphery 21 0f a'shaft or the like. Referring to the construction shown in be rotated and the oody of the tool held stationary, or the work piece and the body of the tool may be turned in opposite directions relatively to each other, as best suits the conditions under which the tool is to be used.

For the purpose of rotating the tool while the work piece is stationary means are provided for coupling the body 22 with. a rotary shaft, arbor or spindle, which, means, as shown in Figs. 1, 3 and 5 preferably consist of a disk shaped head 23 secured by means of bolts 24 to the rear end of the body 22 and provided with a tubular hub 25 which projects inwardly into the head and is ada ted to receive the head 26 of a driving sha t or spindle 27, and is provided with undercut notches 28 adapted to receive coupling pins 29 upon said driving shaft 27 for the purpose of operatively connecting the supporting body of the tool with this shaft.

If it is desired to hold the body of the tool stationary while the work piece is being turned this may be accomplished by providing the rear end of the body with one or more rearwardly projecting tubular seats or sockets 30 each of which is adapted to receive a restraining pin 31 projecting forwardly from a restraining bracket or head 32, as shown in Fig. 7 which bracket may be mounted in any suitable manner on a stationary support so that the body of the tool is held against rotation.

When employed as a grinding tool for grinding or polishing internal cylindrical surfaces, as shown in Figs. 1-6, a plurality of abrasive members or stones 33 having preferably the form of longitudinal sticks, bars or blocks, are arranged in an annular row around the exterior of the tubular supporting body, six of such abrasive members or stones being employed equi-distant around said body, as shown in Figs. 3 and 5," so that the working faces of these abrasive members or stones face outwardly toward the bore or internal cylindrical surface of the cylinder which is to be ground or polished.

Each of these abrasive members or stones is mounted on a holder 34 which is capable of radial movement or adjustment relative to the axis of the body 22. Although this holder 24 may be variously constructed, the same, as best shown in Figs. 1, 2 and (3, is made of U- shaped form in cross section, so as to provide an outwardly facing longitudinal channel in which the inner longitudinal part of one of the grinding stones is secured by means of a self-hardening material 35 or is otherwise secured therein so as to locate the working face of the tool in a correct technical relation with the axis of the tooli. e. under normal conditions the working face of each stone is parallel with the axis of the body.

Each of the stone holders is mounted on the periphery of the supporting body so as to be capable of radial adjustment thereon for adapting the face of the tool to the cylindrical surface on which it operates, and this holder is also capable of tilting relative to the axis of the tool in order to permit the respective stone to adapt itself to any irregularities in the surface which is being ground, and thereby gradually grind this surface into true cylindrical form.

Although various means may be employed for thus guiding and retaining the stone holders on the supporting body this is preferably accomplished in the case of holders which are mounted on the exterior of the supporting body by providing the exterior of the body at intervals with laterally projecting supporting wings 36 upon the outer side of each of which is secured a base plate 37 by means of screws 38, and providing the outer side of this base plate with a plurality of pairs of guide lugs 39 which receive between them the front and rear ends of one of the stone holders 34.

The latter is permitted to move radially between these guide lugs 39 and also to tilt between the same relative to the axis of the body 22, but longitudinal movement of each stone holder is prevented by means of stop pins 40 projecting laterally from opposite longitudinal sides of the stone holder and engaging with the inner opposing ends of the respective guide lugs 39 between which the stone holder is mounted.

Means are provided for yieldingly drawing the several stone holders inwardly as far as is permissible by the means which adjust the position of these holders relative to the axis of the tool. Although these spring means may be variously constructed the same preferably consist of two garter springs 41 which surround the exterior of the supporting body and each of which engages with the outer side of attaching pins 42- arranged at the corresponding ends of the several stone holders as shown in Figs. 1, 2, 3 and 5.

For the purpose of adjusting the working surfaces of the grindin stones to the cylindrical surface which is to be ground or polished and also to take up wear on these stones and the work piece as the grinding proceeds, an adjusting device is associated with each of the stone holders which in its preferred form is constructed as follows Arranged lengthwise in the supporting body and extending from the front end to the rear end thereof are cylindrical bores 43'. From the front and rear ends of each of these bores 43 radial guideways 44, 45 extend outward'ly through the adjacent part of the supporting body through the respective wing 36 and also through the adjacent base 37 mounted thereon, and opening on the outer side of the latter underneath opposi e ends of the stone holder 34 which is guided between the lugs 39 of the respective base 37, as shown in Fig. 1.

Sliding radially in the guideways 44, 45 are two shifting pins 46, 47 the outer rounded ends of which engage with the back or inner sides of the respective stone holder 34 adjacent to opposite ends thereof, while the round-ed inner ends of these shifting pins engage with the external tapered surfaces of two cones 48, 49 which are arranged within the respective bore 43 and are adapted to be moved lengthwise therein.

These two cones are arranged in a reverse position relative to each other and in the preferred arrangement shown in Fig. 1 they have their small or reduced ends opposing each other so that upon drawing these two cones together they will exert a cam or wedge action simultaneously upon said shifting pins 46, 47 whereby the respective stone holder engaging with the outer ends of these pins will be moved radially outward for adjusting its working surface to the internal cylindrical surface which is to be ground, while upon separating or moving these two cones apart these shifting pins will be permitted to move inwardly toward the axis of the tool and also enable the respective stone holder to also move inwardly for the purpose of disengaging the working face of the stone from the internal cylindrical surface, or for the purpose of contracting the Working diameter of the tool as a whole.

The position of the two cones lengthwise relatively to each other may be adjusted in various ways but preferably by the means which are shown, for example, in Fig. 1, and

which comprise a longitudinal adjusting bolt 50 arranged axially in the respective bore 43 and passing loosely at one end through the front cone 48 and having a screw connection 51 at its other end with the rear cone 49 and provided at its front end with a head 52 which engages with the front end of the front cone.

Upon turning this bolt in one direction the cones are drawn together while upon turning this bolt in the opposite direction and unscrewing the same the cones are permitted to separate.

I Inorder to support the cones at their small ends and prevent these ends together with the adjacent part of the adjusting bolt from being deflected by the pressure which is exerted against the same by the shifting pins upon engaging the stones with the cylindrical surface while the latter is being ground or polished, separate pilot or retaining sleeves 53 are mounted on the adjusting bolt 50 adjacent to the small ends of the cones and engaged at their periphery with the cylindrical wall of the respective bore 43. By this means the cones are sustained at their small ends in axial alignment with each other but are free to move lengthwise in these bores in adjusting or operating the tool.

For the purpose of insuring separation of the two cones to their maximum extent, a separating spring 54 is employed which surrounds the central part of the adjusting bolt and bears at its opposite ends against the opposing sides of the retaining sleeves 53. I upon inserting this tool into engagement with an internal cylindrical surface this surface should be of irregular or untrue form, one or more of the abrading stones may be tilted more or less relative to the'axis of the supporting body as the face of this stone adapts itself to this irregular formation of the cylindrical'surface, and during such tilting or rocking action of the stone carrier one of the shifting pins associated therewith will be moved inwardly toward the axis of the supporting body and thereby exert a wedging action on the respective cone for moving the adjusting bolt and the companion cone in the same direction while the last-mentioned cone will shift the shifting pin in engagement therewith radially outward.

The stone holder will be thus tilted more or less until the irregularity in the surface of the cylinder which is being ground has been trued up, but when the surface which is being ground assumes a true cylindrical form the stone again returns to a position in-which its face is parallel to the axis of the-supporting body and the two adjusting cones associated therewith also will assume their normal position.

For the purpose of preventing the rear cone 49 from turningwhile the adjusting screw 50 is'turned in one direction or-the other for shifting the position of the cones relatively to each other, means are provided which preferably consist of pins or keys 55 mounted on the supporting body and working in a longitudinal slot 156 in the large end of the rear come 49 whereby thelatter is held against turning but permitted to slide lengthwise.

- Means are provided whereby the adjusting devices of all the stone carriers or holders may be adjusted simultaneously relatively to the axis of the supporting body in order to preserve the cylindrical form of the grinding zone of these stones.

This is preferably accomplished by providing the head 52 at the front end of each adjusting bolt 50 with an adjusting gear pinion 56 andengaging the inner sides of these several gear pinions by a rotary gear ring 57 which is rotata ly mounted on the front end of the supporting body 22. The support for this ring consists preferably of a plurality of bearing lugs 58 arranged on the front end of this supporting body and engaging with the rear or inner side of the gear ring 57, and a plurality of retaining clips 59 of L-shaped form, each of which has one of its legs secured to the periphery of the supporting body 22 by means of screws 60, while its other leg engages with the front side of the gear ring 57, as best shown in Figs. 1, 2, 3 and 4.

,Upon turning. this gear ring or any one of the gear pinions meshing therewith, the several gear pinions are turned in unison together with the adjusting bolts 50 with which these gear pinions are connected, thereby permitting of simultaneously adj usting the several pairs of cones associated with the stone holders and causing all the faces of the stones to be maintained in the same position relative to the axis of the supporting body.

In the preferred construction the rotation of the several gear pinions for adjusting the position of the stone holders isefi'ected by manually turning one of the gear pinions whereby the gear ring is turned and causes the remaining gear inions to be turned in the same measure. s shown in Fig. 1, these means comprise an adjusting stem 61 projecting forwardly from one of the gear pinions 56 and provided at its front end with a fiat sided portion 62 which is adapted to receive a detachable crank, wrench or key 63 whereby this particular gear pinion may be rotated in one direction or the other and the remaining gear pinions may be rotated in -ed lengthwise of its axis in following the changing position of the companion adjustinghbolt 50 and the parts associated therewit For the purpose of supporting each of the gear pinions in mesh with the gear ring 57 and preventing disengagement thereof while the tool is under pressure while in use, the outer side of each of these pinions which is arranged opposite to the gear ring 57 is enaged with a partial bearing 64 of segmental form and pro ecting from the adjacent marginal part of the supporting body 22, as shown in Figs. 1, 2 and 3.

For the purpose of enabling the operator to adjust the instrument with greater facility means are provided for indicating the circumferential position of that gear pinion which is adapted to be turned manually by means of the crank 63, which indicating means preferably consist of a dial, wheel or disk 65 arranged on the adjusting stem 61 and provided on its periphery with graduatons 66 which are adapted to be traversed by a pointer 167 on the adjacent part of the supporting body 22.

When this tool is organized for grinding or polishing external cylindrical surfaces such as the periphery of shafts or the like, the stone carriers or holders and the means for guiding the same on the periphery of the supporting body are removed therefrom together with the shifting pins and then an annular row of abrasive members or stones 68 are mounted in an annular row on the inner side of the supporting body 22 so that the faces of these stones are turned inwardly or toward the axis of this body, as shown in Figs. 7-11. Each of these stones is mounted on its outer side in a holder or carrier 68 which is constructed substantially like the carriers 34 which are employed for supporting the stones which are utilized for boring internal cylindrical surfaces, and each of these carriers engages at opposite ends of its outer longitudinal side against shifting pins 69, 70 which are guided in a pair of radial openings 71, 72 formed on the inner parts of the supporgng body 22 and open at their outer ends into the bore 43 of the respective stone holder adjusting device so that these guideways or openings 71, 72 are in line respectively with the companion openings 44 and 45 and thereby permit the outer ends of the shifting pins 69 and 70 to bear against the inner sides of the same cones 48 and 49 which are engaged by the inner ends of the pins 46 and 47 when the tool is organized for grinding internal cylindrical surfaces.

In this reorganized form of the tool for use in effecting grinding or polishing of external cylindrical surfaces the opposite ends of each stone holder are guided in radial guide slots 73, 74 formed in guide rings 75, 76 which are secured to the front and rear ends of the supporting body 22 by means of screws or bolts 77, 7 8, and longitudinal movement of each of these stone holders is prevented by means of stop pins 79, 80 projecting laterally from opposite sides of this stone holder adjacent to opposite ends thereof and adapted to engage with the inner sides of the guide rings 75, 76 on opposite sides of the guide slots 73, 74 therein, as best shown in Figs. 8 and 10.

Spring means are employed which yieldingly hold the several stone holders outward- IV in engagement with the shifting pins 69 and 70, which spring means preferably consist of two garter springs 81, 82 arranged adjacent to the front and rear ends of the supporting body 22 and each of these springs being bent into zig-zag form and engaging alternately with the outer side of supporting rolls or spools 83 mounted on the fastening screws or bolts 77 78, and the inner sides of retaining pins 84 arranged at the corresponding ends of the stone holders, as best shown in Figs. 1-9 and 11.

In the preferred construction the sockets 30 on the rear side of the supporting body 22 which are adapted to engage the studs 31 of the controlling bracket 32 are preferably made in the form of rearward extension of some of the bores 43 while the rear ends of the remaining bores 43 are closed by means of covering plates 85, as shown in Figs. 1, 5, 7 and 9.

The operation of each of the adjusting devices associated with a stone holder or carrier in this reorganization of the mechanism for producing external cylindrical grinding is substantially the same as when grinding of internal cylindrical surfaces is being done, that is to say-a tightening of the adjusting bolt 50 will cause the cones 48 and 49 to be moved toward each other and thereby move the corresponding stone carrier inwardly toward the surface of the work piece which is to be operated upon, while turning of the bolt 50 in the opposite direction will permit these cones to separate and allow the respec tive stone carrier to move radially outward away from the surface which is being dressed. If the cylindrical surface which is being worked upon is more or less irregular each of the stone carriers is permitted to tilt with reference to the axis of the supporting body in order to adapt the face of the stone to this irregular surface, and during such tilting one of the shifting pins will be moved inwardly and the other one will be moved outwardly as the two cones 48 and 49 shift their position lengthwise under the pressure of the outwardly moving pin.

After the irregular surface on the exterior of the cylinder has been trued up the faces of the several stones again assume a position parallel with the axis of the supporting body so that the operation of grinding this surface may proceed and permit of finishing the same in true cylindrical form.

While the tool is thus operating upon a cylindrical surface the same may be either reciprocated lengthwise of its axis and the work piece held against longitudinal movement, or the tool may be simply rotated and the work piece reciprocated lengthwise,or if desired, both the tool and the work piece may be reciprocated lengthwise in opposite directions so as to enable the cylindrical surface to be ground or polished throughout the length thereof.

The bases 37 provided with the guide lugs 39, as shown in Figs. 1, 2, 3, 5 and 6 will serve to guide the stone holders therein radially with reference to the axis of the supporting body when grinding internal cy lindrical surfaces within a certain range, but when it is desired to bore internal cylindrical surfaces having a diameter which is smaller or greater than the range of the devices which serve to guide the stone holders shown in these particular figures, then these radial guiding devices forthe stone holders are replaced with others which will guide the stone holders either nearer the axis of the supporting body or farther awa from the same. I

In like manner, the guide rings 75 which are mounted on the interior of the supporting body 22 for the purpose of radially guiding the stone carriers 68 and eflecting grinding of external cylindrical surfaces may be made of larger or smaller diameter so as to bring the stone carriers either farther away or nearer to the axis of the supporting body, in accordance with the diameter of the article which is to be ground. For instance, as shown by full lines in Figs. 7, 9, and 10 the guide rings 75 are made comparatively large thereby adapting them as uides for grinding external cylindrical suraces of comparatively large diameter, but when these guide rings 75 are replaced with others having radialguide slots for the stone holders 68 arranged nearer the center of the tool, as shown by dotted lines in Fig. 11, it is possible to control the radial movement of the stone carriers or holders when grinding external cylindrical surfaces of correspondingly smaller diameter.

When usingeither largeor small sizes of guiding devices on the exterior or interior of the supporting body 22 for guiding the stone holders while grinding cylindrical surfaces varying considerably in diameter, it is also necessary to replace the particular shifting pins 46, 47 and- 69, 70 for others which are either longer or shorter in order to reach from the several adjusting cones 48, 49 to the backs of the several stone holders, thereby enabling the same adjusting cones and the parts associated therewith to be utilized at all times regardless of the particular diameter of the cylindrical surface which is being ground.

The main parts of this grinding device are therefore standard equipment which permits of grinding cylindrical surfaces varying widely in diameter by merely selecting stone holder guiding devices of appropriate size and mounting the same on the supporting body in the manner set forth, thereby enabling a wide range of various cylindrical surfaces to be ground and polished at comparatively small expense for equipment.

By constructing this grinding apparatus so that an individual adjusting device is associated with each of the abrasive members it is possible to make this apparatus suitable for grinding cylindrical surfaces of comparatively large diameter and yet avoid making the same unduly heavy, thereby reducing the cost of the toool and also enabling the same to be operated with a minimum amount of power and also adjusted easily and conveniently for doing this class of work.

I claim as my invention 1. A grinder for cylindrical surfaces comprising a rotatable supporting body, and means for mounting abrasive members on said body for grinding either external or internal cylindrical surfaces including outer and inner radial guideways formed on the outer and inner parts of said body; stone holders adapted to be slid in said guideways toward and from the axis of the tool, and ad usting means mounted on said body between said outer and inner guideways and adapted to shift said stone holders radially.

2., A grinder for cylindrical surfaces comprising a ring shaped supporting body havlng means on its inner side for mounting thereon abrasive members adapted to effect grinding of external cylindrical surfaces and means on its outer side for mounting thereon abrasive members adapted to effect grinding of internal cylindrical surfaces and means mounted on said body for adjusting said abrasive members radially on said body.

A grinder for cylindrical surfaces comprisln-g a ring shaped supporting body having means on its inner side for mounting thereon external grinding abrasive members adapted to effect grinding of external cylindrical surfaces and means on itsouter side for mounting thereon internal grinding abrasive members adapted to effect grinding of internal cylindrical surfaces, and means mounted on said body for radially adjusting on said body either the internal grinding or the external grinding abrasive members.

4. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive members arranged in an annular row relative to the axis of said body and guided thereon for radial movement, and

a plurality of individually operating adj usting devices mounted on said body and each cooperating wlth one of said abrasive members independently of the other members for shifting the same radially relatively to the axis of said body and holding the same positively against movement away from the surface which is being ground.

5. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive members arranged in an annular row relative to the axis of said body and guided thereon for radial movement, a plurality of individually operating adjusting devices mounted on said body and each cooperating with one of said abrasive members independently of the other members for shifting the same radially relatively to the axis of said body and holding the same positively against movement away from the surface which is being ground, and means for operating said adjusting devices simultaneousl 6. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, and a plurality of adjusting devices mounted on said body and each including opposed floating cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground.

7. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of adjusting devices mounted on said body and each including opposed floating cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground, and spring means for holding the several abrasive carriers yieldingly in engagement with said cones.

8. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of adjusting devices mounted on said body and each including opposed floating cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground, and garter springs engaging with opposite ends of the several abrasive carriers and operating to hold the same yieldingly in engagement with said cones.

9. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plu-- rality of abrasive carriers guided for radial adjustment on said body, a plurality of adjusting devices mounted on said body and each including opposed cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground, a screw bolt connecting the cones of each adjusting device, and means for simultaneously turning the bolts of the several adjusting devices.

10. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of adjustable devices mounted on said body and each including opposed cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground, a screw bolt connecting the cones of each adjusting device, and means for simultaneously turning the bolts of the several adjusting devices, including gear pinions arranged on said bolts, and a gear ring mounted on said body and meshing with the several gear pinions.

11. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of adjusting devices mounted on said body and each including opposed cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground, a screw bolt connecting the cones of each adjusting device, and means for simultaneously turning the bolts of the several adjusting devices, including gear pinions arranged on said bolts, a gear ring mounted on said body and meshing with the several gear pinions, one of said gear pinions being provided with an adjusting stem adapted to receive a crank.

12. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of adjusting devices mounted on said body and each including opposed cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground, a screw bolt connecting the cones of each adjusting device, and means for simultaneously turning the bolts of the several adjusting devices, including gear pinions arranged on said bolts, a gear ring mounted on said body and meshing with the several gear pinions, one of said gear pinions being provided with an adjusting stem adapted to receive a crank, a dial on said stem, and a pointer on said body adapted to traverse said dial.

13. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of adjusting devices mounted on said body and each including opposed cones which engage ,j opposite ends of one of said carriers and J which are connected to resist movement of the respective abrasive carrier away from the surface being ground, a screw bolt connecting the cones of each adjusting device, and means for simultaneously turning the bolts of the several adjusting devices including gear pinions arranged on said bolts, a gear ring mounted on said body and meshing with the several gear pinions, and a plurality of clips arranged on said body and engaging with said gear ring for holding the latter in position.

14. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of ad justing devices mounted on said body and each including opposed cones which engage opposite ends -of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surface being ground, a screw bolt connecting the cones of each adjusting device, and means for simultaneously turning the bolts of the several adjusting devices including gear pinions arranged on said bolts, a gear ring mounted on said body and meshing with the several gear pinions, each of said gear pinions being elongated to permit the same to move lengthwise to a certain extent with the respective adjusting bolt and still remain in mesh with said gear ring.

15. A grinder for cylindrical surfaces comprising a rotatable supporting body, a plurality of abrasive carriers guided for radial adjustment on said body, a plurality of adjusting devices mounted on said body and each including opposed cones which engage opposite ends of one of said carriers and which are connected to resist movement of the respective abrasive carrier away from the surfacebeing ground, a screw bolt connecting the cones of each adjusting device, and means for simultaneously turning the bolts of the several adjusting devices, including gear pinions arranged on said bolts, :1 gear ring mounted on said body and meshing with the several gear pinions, each of said gear pinions being elongated to permit the same to move lengthwise to a certain extent with the respective adjusting bolt and still remain in mesh with said gear ring, and said body being provided with elongated bearings engaging the sides of said gear pinions.

16. A grinder for cylindrical surfaces comprising a rotatable supporting body provided with an annular row of longitudinal bores vided with an annular row of longitudinal bores and radial guideways opening into said bores, a plurality of abrasive carriers guided for radial movement on said body, adjusting pins sliding'radially in said guideways and engaging their outer ends with said abrasive carriers, opposing adjusting cones arranged in each of said bores and engaging the shifting pins of the respective abrasive carrier, an adjusting screw bolt connecting the cones in each of said bores, and pilot sleeves arranged in each of said bores at the small end of the cones therein, and movable therewith.

18. A grinder for cylindrical surfaces comprising a rotatable supporting body provided with an annular row of longitudinal bores and radial guideways opening into said bores, a plurality of abrasive carriers guided for radial movement in said body, adjusting pins sliding radially in said guideways and engaging their outer ends with said abrasive carriers, opposing adjusting cones arranged in each of said bores and engaging the shifting pins of the respective abrasive carrier, an adjusting screw bolt connecting the cones in each of said bores, pilot sleeves arranged in each of said bores at the small end of the cones therein and movable therewith, and a spring surrounding each of said bolts and engaging with the respective pilot sleeves.

19. A grinder for cylindrical surfaces comprising a rotatable supporting body provided with an annular row of longitudinal bores and radial guideways opening into said bores, a plurality of abrasive carriers guided for radial movement on said body,

adjusting pins sliding radially in said guide-.

ways and engaging their outer ends with said abrasive carriers, opposing adjusting cones arranged in each of said bores and engaging the shifting pins of the respective abrasive carrier, an adjusting screw bolt connecting the cones in each of said bores, guide members arranged on said body on opposite sides of each abrasive carrier, and stop pins'ar-' ranged on each abrasive carrier and engaging with said guide members for restraining longitudinal movement of abrasive carriers relative to said body.

, In testimony whereof I hereby aifix my signature. MARSDEN C. HUTTO.

and radial guideways opening into said N bores, a pluralityof abrasive carriers guided for radial movement on said body, adjusting pins sliding radially in said guideways and engaging their outer ends with said abrasive carriers, opposing adjusting cones arranged in each of said bores and engaging the shift- 

